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[perl #113928] caller behaving unexpectedly in re-evals

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From:
Father Chrysostomos
Date:
July 1, 2012 13:55
Subject:
[perl #113928] caller behaving unexpectedly in re-evals
Message ID:
rt-3.6.HEAD-28836-1341176131-388.113928-75-0@perl.org
# New Ticket Created by  Father Chrysostomos 
# Please include the string:  [perl #113928]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=113928 >


If code blocks in regular expressions are supposed to be analogous to sort blocks, then I could expect these to return the same thing:

$ ./perl -Ilib -le '$,=" "; sub foo { @_ = sort {print caller 0 } 1..2 } foo()'
main -e 1 main::foo 1    256  
$ ./perl -Ilib -le '$,=" "; sub foo { /(?{ print caller 0 })/ } foo()'
main -e 1 main::foo     256  

The only difference here is the 1 after the sub name ($has_args).

I get yet another set of results with a qr// thing:

$ ./perl -Ilib -le '$,=" "; sub foo { ""=~qr/(?{ print caller 0 })/ } foo()'
main -e 1 main::__ANON__     256  

If I change caller 0 to caller 1, I get this:

$ ./perl -Ilib -le '$,=" "; sub foo { @_ = sort {print caller 1 } 1..2 } foo()'

$ ./perl -Ilib -le '$,=" "; sub foo { /(?{ print caller 1 })/ } foo()'
main -e 1 main::foo 1    256  
$ ./perl -Ilib -le '$,=" "; sub foo { ""=~qr/(?{ print caller 1 })/ } foo()'
main -e 1 main::foo 1    256  

That a regexp code block inside foo should appear like a &foo call is weird.  That it should show main::foo, while qr shows main::__ANON__, just seems inconsistent.

The implementation is leaking through.  I think the regexp blocks should simply not be counted as call frames.  I know how to fix this.  I just wanted to check first.

On a related note:

$ ./perl -Ilib -e 'sub foo { ""=~qr/(?{CORE::__SUB__->()})/ } foo'
Bus error

That was how I discovered this.

---
Flags:
    category=core
    severity=low
---
Site configuration information for perl 5.17.2:

Configured by sprout at Mon Jun 25 13:28:03 PDT 2012.

Summary of my perl5 (revision 5 version 17 subversion 2) configuration:
  Snapshot of: 256aa5e6f36285b09b3ba67ad9926c9d4f9ea7bc
  Platform:
    osname=darwin, osvers=10.5.0, archname=darwin-2level
    uname='darwin pint.local 10.5.0 darwin kernel version 10.5.0: fri nov 5 23:20:39 pdt 2010; root:xnu-1504.9.17~1release_i386 i386 '
    config_args='-de -DDEBUGGING -Dusedevel'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=undef, usemultiplicity=undef
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=undef, use64bitall=undef, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-fno-common -DPERL_DARWIN -DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include',
    optimize='-O3 -g',
    cppflags='-fno-common -DPERL_DARWIN -DDEBUGGING -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.2.1 (Apple Inc. build 5664)', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='env MACOSX_DEPLOYMENT_TARGET=10.3 cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /usr/lib
    libs=-ldbm -ldl -lm -lutil -lc
    perllibs=-ldl -lm -lutil -lc
    libc=, so=dylib, useshrplib=false, libperl=libperl.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=bundle, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags=' -bundle -undefined dynamic_lookup -L/usr/local/lib -fstack-protector'

Locally applied patches:
    

---
@INC for perl 5.17.2:
    /usr/local/lib/perl5/site_perl/5.17.2/darwin-2level
    /usr/local/lib/perl5/site_perl/5.17.2
    /usr/local/lib/perl5/5.17.2/darwin-2level
    /usr/local/lib/perl5/5.17.2
    /usr/local/lib/perl5/site_perl
    .

---
Environment for perl 5.17.2:
    DYLD_LIBRARY_PATH (unset)
    HOME=/Users/sprout
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/local/bin
    PERL_BADLANG (unset)
    SHELL=/bin/bash


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